Crucible-furnace.



PATENTBD JAN. so, 1906.

E. HAUSMANN. GRUGIBLE FURNAGE. APPLICATION FILED AUG.19, 1905.

- A WC/ff uf N\ rhs iria Specification of Letters Patent.

Patented Jan. 30, 1906.

Application filed August 19, 1905. Serial No. 274,951.

To all whom it may concern.-

Be itknown that I, ERNST HAUSMANN, a subject of the German Emperor, residing at Cologne, Germany, have invented new and useful Improvements in Crucible-Furnates, of which the following is a specification.

Crucible-furnaces are as a rule provided with air-passages formed in the walls of the furnace-shaft, which passages are traversed by the air to be introduced, whereupon the latter passes under the grate suitably heated. The temperatures ruling in these air-pasSages of the furnace-shaft are not uniform at all parts, so that the heat imparted to the air passing through them differs very much at different places. In view of the latter circuinstance the present invention endeavors to solve the problem of passing the air in such a way through the passages of the furnace-shaft that the transmission of heat to the air is the most Jfavorable possible under the existing variations of temperature. In order to attain this, I start from the well-known fact that the most favorable transmission of heat to the medium to be heated takes place when the latter is passed in counter-current to the heat radiation-that is to say, always from the places of lower temperature to the places of higher temperature. The greatest heat in a crucible-furnace is evolved, as is well known, at a certain distance above the grate. From this zone of the greatest heat the temperature decreases also in the air-supply passages upward and downward. Accordingly by the present invention the air is passed through the passages of the furnaceshaft 'from both ends of the latterthat is to say, both from the upper and also from the lower end-against the radiation lof the heat up to the zone of the greatest heat-that is to say, to close above the grate. In this Zone the air to be heated in the passages is somewhat held back by suitable means-for instance, by partitions, which force it to llow round them-and after in this manner the highest attainable heating value of the heat transmission is obtained the air thus preliminarily heated is conveyed under the grate in order to reach the fire, then through the grate.

One form of construction of the invention is shown in the accompanying drawings.

Figures 1 and 2 are two longitudinal sections, at right angles to one another, of the improved crucible-furnace. Fig. 3 is a s ection on the lineAA of Fig. l; Fig. 4, a section on the line B B of Fig. 2.

The masonry furnace-shaft a has in the forni of construction shown a square section and is surrounded by a sheet-imetal casing l). Between the latter and the masonry a there are air-supply passages c. The air, as shown by the arrows in Fig. 1, is conducted both from the upper as well as from the lower end of the passages c to the hottest zone A A, which lies a short distance above thegrate d. The passages c are closed on the vertical narrow sides, as shown more particularly in Fig. 3, the masonry of the rear and front wallsof the furnace-shaft being prolonged at the side up to the sheet metal casing b. IBy this means the passages c are separated from the passages e. The lateral prolongations above mentioned of the masonry are provided in the zone A A with apertures f. By means of these apertures the blast can pass through these apertures after it has reached the hottest zone A A against the heat radiation and pass into the air-supply passages c. The size of the apertures f may be such that the air is somewhat retained in the hottest zone, so that it becomes suitablyheated. In order to further retain the air at this place, partitions g and 7L, formed of sheet metal, are a rranged in the form of construction shown in the passages e, along which partitions the air is forced to flow. If necessary, such partitions inay also be provided in the passages. After the air iiowing against the heatradiation is suitably preliminarily heated in this manner it flows downward, as shown in Figs.

l and 2, out of the passages c and passes i through apertures 7c, formed in the walls e of the ashepit into the space lyingl beneath the grated in order then to pass to the fire through the grate.

I declare that what I claim is- A crucible-furnace having air-feed passages formed in the walls thereof, said passages having inlet-openings at the lower and upper IOO ends thereof, a lateral passage situated at a In testimony whereof I have signed my point a short distance above the plane ofthe name to this speeioation in the presence of grate and connected to the feed-passages, two subscribing Witnesses. means for retardin@ the air in said lateral pas- ERNST HAUSMANN.

5 sage and assages For conducting the air from Witnesses:

the latera passage to beneath the grate, sub- BEssIE F.l DUNLAP, stantially as described. LoUIs VANDORY. 

